Influence of the Impurities on Cathodic Copper on the Ductility of Copper Wires

Abstract:

The main characteristic of cathodic copper is the concentration of impurities because it depends on mechanical characteristics, i.e. ductility, of the derived copper wires. The standard mechanical tests that evaluate their ductility, are quick elongation and spiral elongation tests. The results of these essais shown that there is not a clear correlation among the impurities content in cathodes and wire ductility. Also, the two mechanical tests actually used are not able to discriminate differences on the copper ductility associated to variations in impurities concentration, at ppm level. In this work, a design of new specimen for traction test, with a reduced gage length of 10 mm that clearly discriminate differences on copper ductility associated to variations in impurities concentration is exposed. In addition, from traction tests to copper wires and observation of their fracture surfaces by means of SEM and EDS it is concluded that the principal impurity affecting the ductility of the copper wires is the oxygen, mainly incorporated during the melting of the cathodes and casting of the rods. Also, the traditional annealing to the samples previous to the tensile tests must to be avoid since produces a dispersion on the matrix of the Cu₂O oxides and so the deleterious effect of the oxygen on the copper ductility cannot be detected.

• Periodical: Materials Science Forum (Volumes 706-709)
• Pages: 899-906
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.706-709.899
• Online since: January 2012
• Authors: Carlos Camurri, Claudia Carrasco, Antonio Pagliero, Rodrigo Leite
• Keywords: Cathodic Copper, Ductility Copper Wires, Impurity, Mechanical Test

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